Call forwarding



anyone have issues turning call forwarding on?  I signed up a few months ago and purchased a brand new iPhone 12 from Shaw.  I’ve never been able to activate call forwarding.  When it turn it on I get promoted for the number, I put the number in to forward to and go back and the feature just turns off.  If I try to do it using *21* and the number # I just get unknown error.  

I had a call with Shaw support, they tried a bunch of stuff and then said they were investigating. It’s been a few weeks and now they closed the call with no fix.  Only suggestion was to ask Apple support. I asked Apple and they say it’s probably a Shaw network issue, not IOS issue.  

any ideas?